Oral Pathobiont Activates Anti-Apoptotic Pathway, Promoting both Immune Suppression and Oncogenic Cell Proliferation. Issue 1 (December 2018)

• Record Type: Journal Article
• Authors: Arjunan, Pachiappan; Meghil, Mohamed; Pi, Wenhu; Xu, Jinxian; Lang, Liwei; El-Awady, Ahmed; Sullivan, William; Rajendran, Mythilypriya; Rabelo, Mariana; Wang, Tong; Tawfik, Omnia; Kunde-Ramamoorthy, Govindarajan; Singh, Nagendra; Muthusamy, Thangaraju; Susin, Cristiano; Teng, Yong; Arce, Roger; Cutler, Christopher
• Is Part Of: Scientific reports. Volume 8:Issue 1(2018)
• Page Start: 1
• Page End: 15
• Publication Date: 2018-12
• Subjects: Natural history -- Research -- Periodicals; Biology -- Research -- Periodicals; Physical sciences -- Research -- Periodicals; Earth sciences -- Research -- Periodicals; Environmental sciences -- Research -- Periodicals; 502.85
• DOI: 10.1038/s41598-018-35126-8
• Languages: English
• ISSNs: 2045-2322

Abstract

Abstract Chronic periodontitis (CP) is a microbial dysbiotic disease linked to increased risk of oral squamous cell carcinomas (OSCCs). To address the underlying mechanisms, mouse and human cell infection models and human biopsy samples were employed. We show that the 'keystone' pathogenPorphyromonas gingivalis, disrupts immune surveillance by generating myeloid-derived dendritic suppressor cells (MDDSCs) from monocytes. MDDSCs inhibit CTLs and induce FOXP3 + Tregs through an anti-apoptotic pathway. This pathway, involving pAKT1, pFOXO1, FOXP3, IDO1 and BIM, is activated in humans with CP and in mice orally infected with Mfa1 expressingP. gingivalis strains. Mechanistically, activation of this pathway, demonstrating FOXP3 as a direct FOXO1-target gene, was demonstrated by ChIP-assay in human CP gingiva. Expression of oncogenic but not tumor suppressor markers is consistent with tumor cell proliferation demonstrated in OSCC-P. gingivalis cocultures. Importantly, FimA + P. gingivalis strain MFI invades OSCCs, inducing inflammatory/angiogenic/oncogenic proteins stimulating OSCCs proliferation through CXCR4. Inhibition of CXCR4 abolishedPg -MFI-induced OSCCs proliferation and reduced expression of oncogenic proteins SDF-1/CXCR4, plus pAKT1-pFOXO1. Conclusively, P. gingivalis, through Mfa1 and FimA fimbriae, promotes immunosuppression and oncogenic cell proliferation, respectively, through a two-hit receptor-ligand process involving DC-SIGN+hi /CXCR4+hi, activating a pAKT+hi pFOXO1+hi BIM−low FOXP3+hi and IDO+hi - driven pathway, likely to impact the prognosis of oral cancers in patients with periodontitis.